In Japan, experts say biggest fallout-related risk is thyroid cancer

While experts are saying that North Americans are unlikely to be affected by radiation leaks in Japan, they are noting that Japanese citizens may have a higher risk of thyroid cancer.

The recent Tohoku earthquake, which damaged a number of nuclear power plants on the East Coast of Japan, is expected to have caused the release of massive amounts of radioactive fallout, according to Reuters.

A toxicologist at the Chinese University of Hong Kong's School of Medical Sciences told the news service that the waters in and around the Fukushima I and II power plants - not to mention those in the general vicinity of Japan - must be measured for the presence of radiation.

Experts have been quoted in the news source comparing the recent radiation leaks to the Chernobyl nuclear disaster of 1986, an event that the United Nations recently connected to more than 6,000 subsequent cases of thyroid cancer.

The newest radiation leaks in Japan, caused by earthquake- and tsunami-triggered explosions in nuclear power facilities, may have a similar effect, some health officials are warning.

The Japan Atomic Energy Agency initially gave the Fukushima I explosion a rating of four on the International Nuclear and Radiological Event Scale. However, more recent estimates by radiology experts have informally nudged the event toward a six, CNN News reports. Chernobyl is currently the only disaster to be rated a seven - the most severe disaster level.

Thyroid cancer is currently the main public health risk related to this event, the UK Press Association notes.

Among other radioactive isotopes created by the power plant blast, iodine-131 may have been released into the immediate vicinity. Children are at the highest risk for developing thyroid cancer from iodine-131 fallout, which can stay in drinking water and cow's milk for up to three months, the news source adds.

Reuters Africa reports that many Japanese citizens are being given potassium iodide, a common salt that loads the thyroid gland with non-radioactive iodine, preventing it from absorbing iodine-131.